There was one left here - yes, just one - in an old sink in the garden. The previous owners moved to a flat and hadn't really thought about it
The first job we had done was the double glazing downstairs, and as luck would have it one of the guys doing it had a great big pond and was more than happy to bring his net and take it
The sink now has herbs planted in it, but there were also toads and at least one of those is still around.